Reinforced foam laminates and a process for their manufacture

Abstract

The laminates have a core of rigid isocyanurate-based foam sandwiched between two facing sheets which are preferably non-combustible. Embedded in the core, substantially throughout its thickness, are multiple layers of a mesh of continuous glass fibre strands which is readily permeable to the foam forming ingredients. Each layer of the mesh is substantially parallel to the facing sheets. The laminates show advantages over laminates reinforced with single filament surface veil mat, single filament expanded mat, single filament random swirl mat and continuous rovings.

I claim: 
     
       1. A laminated panel comprising a core of rigid isocyanurate-based foam sandwiched between two facing sheets characterized in that a mesh of continuous glass fiber strands readily permeable to the foam forming ingredients is embedded in multiple layers substantially throughout the thickness of the foam core, the whole being bonded together by the foam core into a unitary construction. 
     
     
       2. A laminated panel as claimed in claim 1 in which the glass fibre strands are composed of 50 to 200 filaments of diameter 5 to 30 microns. 
     
     
       3. A laminated panel as claimed in claim 1 in which the glass fibre strands are composed of 50 to 200 filaments of diameter 13 to 17 microns. 
     
     
       4. A laminated panel as claimed in claim 1 in which the glass fibre strands which form the mesh are bound with less than 10% by weight of the binder. 
     
     
       5. A laminated panel as claimed in claim 1 in which the glass fibre strands which form the mesh are bound with less than 2% by weight or less of binder. 
     
     
       6. A laminated panel as claimed in claim 1 in which the mesh is 50 to 350 g/m 2  in weight. 
     
     
       7. A laminated panel as claimed in claim 1 in which the mesh is 75 to 150 g/m 2  in weight. 
     
     
       8. A laminated panel as claimed in claim 1 in which the mesh is 25 Tex Strand Mat of 120 g/m 2  weight. 
     
     
       9. A laminated panel as claimed in claim 1 in which the mesh is 25 Tex Strand Mat of 150 g/m 2  weight. 
     
     
       10. A process for the manufacture of a laminated panel of the type consisting of a core of rigid isocyanurate-based foam sandwiched between two facing sheets, the process comprising contacting an expansible multi-layered mesh of continuous glass fibre strands with an isocyanurate-based rigid foam forming mixture, the mesh being readily permeable to the foam forming ingredients, and allowing the foam to rise and cure between two facing sheets, the panel being formed within a mould or between mould surfaces.